1. Field of the Invention
The invention relates generally to the field of semiconductor manufacturing. More particularly, the invention relates to semiconductor inspection and measurement.
2. Discussion of the Related Art
Inspection and measurement are important areas of semiconductor manufacturing. Measurement may be defined as the ability to precisely quantify physical, dimensional, or electrical properties of different materials. Numerous measurement tools are routinely used to monitor the quality of semiconductor manufacturing processes. Inspection relates to the ability to observe and quantify defects, and inspection tools include a variety of optical instruments used for these purposes. In sub-micron applications, inspection equipment such as scanning electrical microscopes (SEMs) are widely used.
As geometries get smaller, the ability to observe defects in wafers and reticles (masks) becomes more challenging and expensive. Existing wafer and reticle inspection tools find defects which can only be disposed when their location is understood. Typically, engineers spend many hours or days attempting to determine the location of defects in order to be able to classify and judge their impact on production yield. Consequently, defects are often disposed without regard to their location but rather only to its size.
Thus, there is a need for a method and apparatus for defect location, minimizing engineering defect reduction efforts, and improving the forecast of measures such as production yield.